Firefox 3.5.9 is included in OLPC OS 10.1.3 and can be activated from GNOME.

Since OLPC OS 10.1.3 is based on Fedora 11, and Fedora 11 security updates have ceased, there are no further updates to Firefox. Deployments who need a more recent version of Firefox should replace the one in OLPC OS as their build is constructed.